Multi-function device with positioning system and shared processor

• US 7,800,535 B2
• Filed: 08/05/2008
• Issued: 09/21/2010
• Est. Priority Date: 11/01/2002
• Status: Expired due to Term

• Current Assignee: CSR Technology Incorporated (Qualcomm, Inc.)
• Original Assignee: SIRF Technology Incorporated (Qualcomm, Inc.)
• Inventors: Van Roy, Benjamin, Bloebaum, Scott, Chou, Andrew
• Primary Examiner(s): Issing; Gregory C
• Application Number:
  US12/186,398
• Publication Number:
  US 20090102710A1
• Time in Patent Office: 777 Days
• Field of Search: None
• US Class Current: 342/357.77
• CPC Class Codes: G01S 19/25 involving aiding data received from a cooperating element, e.g. assisted GPS
• CPC Class Codes: G01S 19/29 carrier including Doppler, related G01S19/246 takes precedence
• CPC Class Codes: G01S 19/37 Hardware or software details of the signal processing chain
• CPC Class Codes: G01S 5/0036 of measured values, i.e. measurement on mobile and position calculation on base station
• CPC Class Codes: H04B 1/7102 with transform to frequency domain
• CPC Class Codes: H04B 2201/70715 with application-specific features

Abstract

A multi-function device with a positioning function and a real time positioning engine is disclosed. The device contains also a shared processor used by the positioning function and other functions of the device, such as a mobile radio-communication function. The positioning engine performs in real time the most computational intensive calculations of the positioning function, such as downsampling, Doppler mixing and correlation calculations. Since the received signal need not be stored, the memory requirements of the positioning function are significantly reduced if aiding data is available.

Claims

1. A multi-function mobile device capable of radio communication with a data network/multimedia reproduction and determination of a position based on a positioning signal, comprising:

a positioning engine in said mobile device that performs real-time calculations with said positioning signal;

a shared memory coupled to said positioning engine that (1) receives and stores in real time results of said real-time calculations, each said result comprising correlations under a hypothesis relating the position signal with a selected signal source and a selected Doppler shift and (2) acts as a storage memory for said radio communication or multimedia reproduction functions; and

a shared processor coupled to said memory that (1) retrieves and processes said results to generate positioning information, (2) performs communication protocol functions for said radio communication or multimedia reproduction, and (3) dynamically allocates the shared memory in real time as the results are retrieved and processed,

wherein said positioning engine and said shared processor access said memory independently.

2. The device of claim 1, wherein said memory is shared with a co-processor of the mobile device.

3. The device of claim 1, wherein said results are associated with a plurality of source-Doppler pairs and said shared processor allocates a memory block for each source-Doppler pair to store said positioning engine results and said allocated memory block can be later released by the shared processor for its use.

4. The device of claim 2, wherein said positioning engine results are associated with a plurality of source-Doppler pairs and said shared processor allocates a memory block for each source-Doppler pair to store said positioning engine results and said allocated memory block can be later released by the shared processor for its use or use by the co-processor.

5. The device of claim 1, wherein such shared memory is accessed by said positioning engine and said shared processor through a shared memory interface and memory requests by the positioning engine and by the processor have to be arbitrated to allow the positioning engine to access the shared memory to keep up with memory bandwidth requirement of real time calculation of said position signal.

13. The device of claim 1, wherein said positioning engine and said shared processor reside within an integrated circuit.

14. The device of claim 1, wherein said positioning engine and said shared processor reside on separate integrated circuits.

15. The device of claim 1, wherein said shared processor executes an operating system to dynamically allocate said shared memory for storing results of said real-time calculations from said positioning engine and for performing said radio communication or multimedia reproduction functions.

16. The device of claim 1, wherein said shared memory comprises a plurality of memories with different speed and size.

6. A device to process a received positioning signal in real time and to conduct radio communication with a data network or to process multimedia data comprising:

a shared memory between processors;

a first processor coupled to said memory including;

means for downsampling said positioning signal from an intermediate frequency, to yield a baseband signal;

means for mixing and accumulating said baseband signal, to yield an accumulated signal;

means for correlating and accumulating said accumulated signal with a plurality of hypotheses of a reference signal, to yield a plurality of correlation values; and

means for writing said plurality of correlation values to said memory, each correlation written being a correlation calculated under a hypothesis relating the position signal with a signal source and a Doppler shift; and

a second processor coupled to said memory configured to (1) retrieve said plurality of correlation values for further processing to generate positioning information, (2) conduct said radio communication or multimedia processing, and (3) dynamically allocate said memory in real time,

wherein said first processor and said second processor access said memory independently.

7. A multi-function mobile device capable of radio communication with a data network or multimedia reproduction and determination of a position based on a positioning signal, comprising:

a positioning engine in said mobile device that performs real-time correlation of said positioning signal with a plurality of code phases of a plurality of source-Doppler pairs to generate a plurality of primitive correlation results wherein each of the plurality of said source-Doppler pairs comprises a reference code from a hypothesized signal source and a hypothesized Doppler frequency;

a shared memory coupled to said positioning engine that (1) receives and stores in real time said plurality of primitive correlation results in a plurality of dynamically allocated memory blocks and (2) acts as a storage memory for said radio communication or multimedia reproduction functions;

a shared processor coupled to said memory that (1) retrieves and processes said plurality of primitive correlation results to generate positioning information, (2) performs communication protocol functions for said radio communication or multimedia reproduction, and (3) dynamically allocates said plurality of memory blocks in real time as the plurality of primitive correlation results are retrieved and processed,

wherein said positioning engine and said shared processor access said memory independently.

8. The device of claim 7, wherein said memory is shared with a co-processor of the mobile device.

9. The device of claim 7, wherein said shared processor allocates a memory block for each of the plurality of said source-Doppler pairs to store said primitive correlation results and said allocated memory block can be later released by the shared processor for its use.

10. The device of claim 7, wherein said plurality of dynamically allocated memory blocks is fragmented and a memory pointer is allocated for the position engine to access each of said plurality of memory blocks.

11. The device of claim 7, wherein such shared memory is accessed by said positioning engine and said shared processor through a shared memory interface and memory requests by the positioning engine and by the processor have to be arbitrated to allow the positioning engine to access the shared memory to keep up with memory bandwidth requirement of real time calculation of said plurality of primitive correlation results.

17. The device of claim 7, wherein said positioning engine and said shared processor reside within an integrated circuit.

18. The device of claim 7, wherein said positioning engine and said shared processor reside on separate integrated circuits.

19. The device of claim 7, wherein said shared processor executes an operating system to dynamically allocate said shared memory for storing said plurality of primitive correlation results and for performing said radio communication or multimedia reproduction functions.

20. The device of claim 7, wherein said shared memory comprises a plurality of memories with different speed and size.

12. A device to process a received positioning signal in real time and to conduct radio communication with a data network or to process multimedia data comprising:

a shared memory between processors;

a first processor coupled to said memory comprising;

means for downsampling said positioning signal from an intermediate frequency, to yield a baseband signal;

means for mixing and accumulating said baseband signal, to yield an accumulated signal;

means for correlating and accumulating said accumulated signal with a plurality of code phases of a reference signal associated with a plurality of source-Doppler pairs, to yield a plurality of correlation values, wherein each of the plurality of source-Doppler pairs comprises a hypothesized signal source and a hypothesized Doppler frequency; and

means for writing said plurality of correlation values to a plurality of dynamically allocated memory blocks of said shared memory; and

a second processor coupled to said memory configured to (1) retrieve and process said plurality of correlation values to generate positioning information, (2) conduct said radio communication or multimedia processing, and (3) dynamically allocate said plurality of memory blocks in real time as said plurality of correlation values are retrieved and processed,

wherein said first processor and said second processor access said memory independently.